Basking sharks are the second-largest species of shark alive today, but are harmless to humans and usually feed on plankton. On an online message board, Cavitt speculated the shark may have been feeding on tiny blue krill and plankton that she saw swimming and jumping out of the water in the same area a few days later.

The sharks are usually found in more temperate waters, so seeing one off the shores of Florida is a rare sight.